use crate::{
    annotation::{Annotation, Annotations, Caller, CallerCat, Sample},
    collection::{vcf::Vcf, HasOutputs, Initialize, Version},
    commands::{
        bcftools::{bcftools_keep_pass, BcftoolsConfig},
        longphase::{LongphaseConfig, LongphaseHap, LongphasePhase},
    },
    config::Config,
    io::{readers::get_gz_reader, vcf::read_vcf},
    positions::{num_to_contig, GenomeRange},
    runners::{run_wait, CommandRun, Run},
    variant::{
        variant::{RunnerVariants, Variants},
        variant_collection::VariantCollection,
    },
};
use anyhow::Context;
use itertools::Itertools;
use log::info;
use rayon::prelude::*;
use serde::{Deserialize, Serialize};
use std::{
    fs::{self},
    io::BufRead,
    path::Path,
    str::FromStr,
};

#[derive(Debug)]
pub struct Savana {
    pub id: String,
    pub passed_vcf: String,
    pub phased_germline_vcf: String,
    pub normal_hp_bam: String,
    pub tumoral_hp_bam: String,
    pub config: Config,
    pub log_dir: String,
}

impl Initialize for Savana {
    fn initialize(id: &str, config: Config) -> anyhow::Result<Self> {
        let log_dir = format!("{}/{}/log/savana", config.result_dir, id);
        if !Path::new(&log_dir).exists() {
            fs::create_dir_all(&log_dir)
                .context(format!("Failed  to create {log_dir} directory"))?;
        }

        // Check for phased germline vcf
        // no required anymore since >= 1.3.0
        let phased_germline_vcf = config.constit_phased_vcf(id);
        if !Path::new(&phased_germline_vcf).exists() {
            LongphasePhase::initialize(id, config.clone())?.run()?;
        }

        let normal_hp_bam = config.normal_haplotagged_bam(id);
        let tumoral_hp_bam = config.tumoral_haplotagged_bam(id);

        let passed_vcf = config.savana_passed_vcf(id);
        fs::create_dir_all(config.savana_output_dir(id))?;

        Ok(Self {
            id: id.to_string(),
            passed_vcf,
            config,
            log_dir,
            phased_germline_vcf,
            normal_hp_bam,
            tumoral_hp_bam,
        })
    }
}

impl Run for Savana {
    fn run(&mut self) -> anyhow::Result<()> {
        // force_or_not(
        //     &self.config.savana_output_vcf(&self.id),
        //     self.config.savana_force,
        // )?;

        let id = &self.id;
        let output_vcf = &self.config.savana_output_vcf(id);
        if !Path::new(&output_vcf).exists() {
            info!("Running Savana v{}", Savana::version(&self.config)?);
            // Check for haplotagged bam
            if !Path::new(&self.normal_hp_bam).exists() {
                LongphaseHap::new(
                    id,
                    &self.config.normal_bam(id),
                    &self.phased_germline_vcf,
                    LongphaseConfig::default(),
                )
                .run()?;
            }

            if !Path::new(&self.tumoral_hp_bam).exists() {
                LongphaseHap::new(
                    id,
                    &self.config.tumoral_bam(id),
                    &self.phased_germline_vcf,
                    LongphaseConfig::default(),
                )
                .run()?;
            }

            let savana_args = [
                // "run",
                "--tumour",
                &self.tumoral_hp_bam,
                "--normal",
                &self.normal_hp_bam,
                "--outdir",
                &self.config.savana_output_dir(id),
                "--ref",
                &self.config.reference,
                "--snp_vcf",
                &self.phased_germline_vcf,
                "--no_blacklist",
                "--threads",
                &self.config.savana_threads.to_string(),
            ];
            let args = [
                "-c",
                &format!(
                    "source {} && conda activate savana && {} {}",
                    self.config.conda_sh,
                    self.config.savana_bin,
                    savana_args.join(" ")
                ),
            ];
            let mut cmd_run = CommandRun::new("bash", &args);
            let report = run_wait(&mut cmd_run).context(format!(
                "Error while running `severus.py {}`",
                args.join(" ")
            ))?;

            let log_file = format!("{}/savana_", self.log_dir);
            report
                .save_to_file(&log_file)
                .context(format!("Error while writing logs into {log_file}"))?;
        }

        // Keep PASS
        if !Path::new(&self.passed_vcf).exists() && Path::new(output_vcf).exists() {
            let report =
                bcftools_keep_pass(output_vcf, &self.passed_vcf, BcftoolsConfig::default())
                    .context(format!(
                        "Error while running bcftools keep PASS for {output_vcf}"
                    ))?;
            let log_file = format!("{}/bcftools_pass", self.log_dir);
            report
                .save_to_file(&log_file)
                .context(format!("Error while writing logs into {log_file}"))?;
        }
        Ok(())
    }
}

impl HasOutputs for Savana {
    fn has_output(&self, id: &str) -> (bool, bool) {
        let output = &self.config.savana_passed_vcf(id);
        let passed = &self.config.savana_passed_vcf(id);
        (Path::new(output).exists(), Path::new(passed).exists())
    }
}

impl Version for Savana {
    fn version(config: &Config) -> anyhow::Result<String> {
        let savana_args = ["--version"];
        let args = [
            "-c",
            &format!(
                "source {} && conda activate savana && {} {}",
                config.conda_sh,
                config.savana_bin,
                savana_args.join(" ")
            ),
        ];
        let mut cmd_run = CommandRun::new("bash", &args);
        let report = run_wait(&mut cmd_run)
            .context(format!("Error while running `savana {}`", args.join(" ")))?;
        let log = report.log;
        let start = log
            .find("Version ")
            .context("Failed to find 'Version ' in the log")?;
        let start_index = start + "Version ".len();
        let end = log[start_index..]
            .find('\n')
            .context("Failed to find newline after 'Version '")?;
        Ok(log[start_index..start_index + end]
            .to_string()
            .trim()
            .to_string())
    }
}

impl CallerCat for Savana {
    fn caller_cat(&self) -> Annotation {
        Annotation::Callers(Caller::Savana, Sample::Somatic)
    }
}

impl Variants for Savana {
    fn variants(&self, annotations: &Annotations) -> anyhow::Result<VariantCollection> {
        let caller = self.caller_cat();
        let add = vec![caller.clone()];
        info!("Loading variants from {}: {}", caller, self.passed_vcf);
        let variants = read_vcf(&self.passed_vcf)
            .map_err(|e| anyhow::anyhow!("Failed to read Savana VCF {}.\n{e}", self.passed_vcf))?;
        variants.par_iter().for_each(|v| {
            annotations.insert_update(v.hash(), &add);
        });
        info!("{}, {} variants loaded.", caller, variants.len());
        Ok(VariantCollection {
            variants,
            vcf: Vcf::new(self.passed_vcf.clone().into())?,
            caller,
        })
    }
}

impl RunnerVariants for Savana {}

pub struct SavanaCNRow {
    pub range: GenomeRange,
    pub segment_id: String,
    pub bin_count: u32,
    pub sum_of_bin_lengths: u32,
    pub weight: f32,
    pub copy_number: f32,
    pub minor_allele_copy_number: Option<f64>,
    pub mean_baf: Option<f64>,
    pub n_het_snps: u32,
}

impl FromStr for SavanaCNRow {
    type Err = anyhow::Error;

    fn from_str(s: &str) -> anyhow::Result<Self> {
        let cells: Vec<&str> = s.split("\t").collect();
        let range = GenomeRange::from_1_inclusive_str(
            cells
                .first()
                .context(format!("Error while parsing contig {s}."))?,
            cells
                .get(1)
                .context(format!("Error while parsing start {s}."))?,
            cells
                .get(2)
                .context(format!("Error while parsing end {s}."))?,
        )
        .map_err(|e| anyhow::anyhow!("Error while parsing range {s}.\n{e}"))?;

        Ok(Self {
            range,
            segment_id: cells
                .get(3)
                .context(format!("Error while parsing segment_id {s}."))?
                .to_string(),
            bin_count: cells
                .get(4)
                .context(format!("Error while parsing bin_count {s}."))?
                .parse()
                .map_err(|e| anyhow::anyhow!("Error while parsing bin_count {s}.\n{e}"))?,
            sum_of_bin_lengths: cells
                .get(5)
                .context(format!("Error while parsing sum_of_bin_lengths {s}."))?
                .parse()
                .map_err(|e| anyhow::anyhow!("Error while parsing sum_of_bin_lengths {s}.\n{e}"))?,
            weight: cells
                .get(6)
                .context(format!("Error while parsing weight {s}."))?
                .parse()
                .map_err(|e| anyhow::anyhow!("Error while parsing weight {s}.\n{e}"))?,
            copy_number: cells
                .get(7)
                .context(format!("Error while parsing copy_number {s}."))?
                .parse()
                .map_err(|e| anyhow::anyhow!("Error while parsing copy_number {s}.\n{e}"))?,
            minor_allele_copy_number: cells
                .get(8)
                .context(format!("Error while parsing minor_allele_copy_number {s}."))?
                .parse::<f64>()
                .map(Some)
                .unwrap_or(None),
            mean_baf: cells
                .get(9)
                .context(format!("Error while parsing mean_baf {s}."))?
                .parse::<f64>()
                .map(Some)
                .unwrap_or(None),
            n_het_snps: cells
                .get(10)
                .context(format!("Error while parsing n_het_snps {s}."))?
                .parse()
                .map_err(|e| anyhow::anyhow!("Error while parsing n_het_snps {s}.\n{e}"))?,
        })
    }
}

pub struct SavanaCopyNumber {
    pub data: Vec<SavanaCNRow>,
}

impl SavanaCopyNumber {
    pub fn load_id(id: &str, config: Config) -> anyhow::Result<Self> {
        let path = config.savana_copy_number(id);
        let reader = get_gz_reader(&path)?;
        let mut data = Vec::new();
        for line in reader.lines() {
            let line = line?;
            if line.starts_with("chromosome") {
                continue;
            }
            let cn: SavanaCNRow = line.parse()?;
            data.push(cn);
        }
        Ok(Self { data })
    }
}

// bin chromosome  start   end perc_known_bases    use_bin tumour_read_count   normal_read_count
pub struct SavanaRCRow {
    pub range: GenomeRange,
    pub perc_known_bases: f32,
    pub use_bin: bool,
    pub tumour_read_count: u32,
    pub normal_read_count: u32,
}

impl FromStr for SavanaRCRow {
    type Err = anyhow::Error;

    fn from_str(s: &str) -> anyhow::Result<Self> {
        let cells: Vec<&str> = s.split("\t").collect();
        let bin = cells
            .first()
            .context(format!("Error while parsing range {s}."))?;

        let range = bin
            .split_once(':')
            .and_then(|(a, b)| {
                b.split_once('_').map(|(b, c)| {
                    GenomeRange::from_1_inclusive_str(a, b, c)
                        .context(format!("Error while parsing range {}", bin))
                })
            })
            .context(format!("Invalid range format: {}", bin))??;

        Ok(Self {
            range,
            perc_known_bases: cells
                .get(4)
                .context(format!("Error while parsing perc_known_bases {s}."))?
                .parse()
                .map_err(|e| anyhow::anyhow!("Error while parsing perc_known_bases {s}.\n{e}"))?,
            use_bin: cells
                .get(5)
                .context(format!("Error while parsing use_bin {s}."))?
                .to_lowercase()
                .parse()
                .map_err(|e| anyhow::anyhow!("Error while parsing use_bin {s}.\n{e}"))?,
            tumour_read_count: cells
                .get(6)
                .context(format!("Error while parsing tumour_read_count {s}."))?
                .parse()
                .map_err(|e| anyhow::anyhow!("Error while parsing tumour_read_count {s}.\n{e}"))?,
            normal_read_count: cells
                .get(7)
                .context(format!("Error while parsing normal_read_count {s}."))?
                .parse()
                .map_err(|e| anyhow::anyhow!("Error while parsing normal_read_count {s}.\n{e}"))?,
        })
    }
}

pub struct SavanaReadCounts {
    pub data: Vec<SavanaRCRow>,
}

impl SavanaReadCounts {
    pub fn load_id(id: &str, config: Config) -> anyhow::Result<Self> {
        let path = config.savana_read_counts(id);
        let reader = get_gz_reader(&path)?;
        let mut data = Vec::new();
        for line in reader.lines() {
            let line = line?;
            if line.starts_with("bin") {
                continue;
            }
            let cn: SavanaRCRow = line.parse()?;
            data.push(cn);
        }
        Ok(Self { data })
    }

    pub fn n_tumoral_reads(&self) -> usize {
        self.data
            .par_iter()
            .map(|c| c.tumour_read_count as usize)
            .sum::<usize>()
    }

    pub fn n_normal_reads(&self) -> usize {
        self.data
            .par_iter()
            .map(|c| c.normal_read_count as usize)
            .sum::<usize>()
    }

    pub fn norm_chr_counts(&self) -> Vec<(String, f64)> {
        let n_tum = self.n_tumoral_reads();
        let n_bins = self.data.len();
        self.data
            .iter()
            .chunk_by(|c| c.range.contig)
            .into_iter()
            .map(|(contig_num, chr_counts)| {
                let chr_counts: Vec<_> = chr_counts.collect();

                let chr_n_bins = chr_counts.len();
                let chr_counts = chr_counts
                    .par_iter()
                    .map(|c| c.tumour_read_count as usize)
                    .sum::<usize>();

                let r = chr_counts as f64 / ((chr_n_bins as f64 * n_tum as f64) / n_bins as f64);
                (num_to_contig(contig_num), r)
            })
            .collect()
    }
}

#[derive(Debug, Serialize, Deserialize)]
pub struct SavanaCN {
    pub segments: Vec<CNSegment>,
}

#[derive(Debug, Serialize, Deserialize)]
pub struct CNSegment {
    pub chromosome: String,
    pub start: u64,
    pub end: u64,
    pub segment_id: String,
    pub bin_count: u32,
    pub sum_of_bin_lengths: u64,
    pub weight: f64,
    pub copy_number: f64,
    pub minor_allele_copy_number: Option<f64>,
    pub mean_baf: Option<f64>,
    pub no_het_snps: u32,
}

impl SavanaCN {
    pub fn parse_file(id: &str, config: &Config) -> anyhow::Result<Self> {
        let path = config.savana_copy_number(id);
        let reader = get_gz_reader(&path)?;
        // let file = File::open(&path).context("Failed to open the file")?;
        // let reader = io::BufReader::new(file);

        let mut segments = Vec::new();

        for (index, line) in reader.lines().enumerate() {
            let line = line.context("Failed to read line from file")?;

            // Skip header line
            if index == 0 {
                continue;
            }

            let parts: Vec<&str> = line.split('\t').collect();
            if parts.len() != 11 {
                return Err(anyhow::anyhow!(
                    "Invalid number of columns at line {} (expected 11, got {})",
                    index + 1,
                    parts.len()
                ));
            }

            // Helper closure for parsing with context
            let parse_field = |field: &str, name: &str, line_num: usize| -> anyhow::Result<f64> {
                field
                    .parse()
                    .context(format!("Failed to parse {name} at line {line_num}"))
            };

            let parse_field_u32 =
                |field: &str, name: &str, line_num: usize| -> anyhow::Result<u32> {
                    field
                        .parse()
                        .context(format!("Failed to parse {name} at line {line_num}"))
                };

            let line_num = index + 1;

            let segment = CNSegment {
                chromosome: parts[0].to_string(),
                start: parse_field_u32(parts[1], "start", line_num)? as u64,
                end: parse_field_u32(parts[2], "end", line_num)? as u64,
                segment_id: parts[3].to_string(),
                bin_count: parse_field_u32(parts[4], "bin_count", line_num)?,
                sum_of_bin_lengths: parse_field_u32(parts[5], "sum_of_bin_lengths", line_num)?
                    as u64,
                weight: parse_field(parts[6], "weight", line_num)?,
                copy_number: parse_field(parts[7], "copy_number", line_num)?,
                minor_allele_copy_number: if parts[8].is_empty() {
                    None
                } else {
                    Some(parse_field(parts[8], "minor_allele_copy_number", line_num)?)
                },
                mean_baf: if parts[9].is_empty() {
                    None
                } else {
                    Some(parse_field(parts[9], "mean_baf", line_num)?)
                },
                no_het_snps: if parts[10].is_empty() {
                    0
                } else {
                    parse_field_u32(parts[10], "no_het_snps", line_num)?
                },
            };

            segments.push(segment);
        }

        Ok(Self { segments })
    }
}